Gaseous electric discharge lamp device



June 11, 1935. c. BOL 2,004,564

GASEOUS ELECTRIC DISCHARGE LAMP DEVICE Filed May 25, 1954 INVENTOR away W178 ATTORNEY Patented June 11, 1935 mrao STATES PATENT OFFICE GASEOUS ELECTRIC DISCHARGE LAMP VICE New York Application May 25, 1934, Serial No. 727,526 In the Netherlands June 3, 1933 2 Claims.

The present invention relates to gaseous electric discharge lamp devices of the positive column type generally and more particularly the invention relates to lamp units comprising such devices having curved, tubular containers the ends of which are in adjacent positions.

The object of the present invention is to provide a lamp unit comprising a gaseous electric discharge device of simple design and which is inexpensive to manufacture. Still further objects of the invention will be apparent from the following detailed description thereof.

The ends of the curved, tubular container, a U-shaped container for example, have inverted stems, that is, the pinched part of each of said stems protrude from said ends. The pinched parts of said ends are flat and lie in the same plane. Both stems can thus be pinched in one operation during the sealing in process of the electrodes. The container is provided with a base of small dimensions which protrudes slightly or not at all from the periphery of the ends of the tube. This is of advantage when the tubular container is mounted in a heat conservator, such as a double walled glass jacket, since the distance between the jacket and the container is then small which is beneficial to the efilciency of the lamp unit.

In the drawing accompanying and forming part of this specification an embodiment of the invention is shown, in which Fig. 1 is a front elevational partly sectional view, and

Fig. 2 is a sectional view along the line 2-2 of Fig. 1.

Referring to the drawing the new and novel lamp unit comprises a gaseous electric discharge lamp device having a U-shaped container I. Each end of said U-shaped container I has a pinch part 2 which protrudes from the end of said container I. As shown in Fig. 2 both of said pinch-parts 2 lie in the same plane and thus both can be formed in one operation during the operation of the device. The container I can thus be made in the following manner. A straight tube is bent in the center thereof in the form of a U. The U-shaped tube is then placed on a sealing machine and the two pairs of electrodes 3 and 4 and the current leads therefor are inserted in their proper positions in the ends of said tube. The ends of the tubes are then heated to the temperature at which they become plastic and are then pinched, closing said ends, sealing the leads therein and forming the pinched parts 2 which protrude from the ends of the container I. The container I is then exhausted of air and a gas, such as neon, at a few mm. pressure and a quantity of vaporizable material, such as sodium, is then introduced into said container I. When the container I is sealed oil from the exhaust system a seal-off tip I4 is formed on said container I. The discharge in the device during the operation thereof is of the positive column type. The electrodes 3 are the cathodes and consist of a metal filament, such as a tungsten 10 or a nickel filament, coated with an electron emitting material, such as barium oxide and said anodes 4 are metal cylinders, such as molybdenum cylinders, open at both ends and surrounding said cathodes 3.

The pinch parts 2 of said container I are inserted in a base 5 of heat resisting, insulating material, such as asbestos cement, and one end only of said container I is attached to said base 5 by a body Ii of heat resisting, insulating cement. 20 The other end of said container I is movable with respect to said base 5 and breaking of the container I due to the expansion and contraction of said container I during the service of the lamp unit is avoided. It will be noted that the rim 25 of the base 5 is but slightly larger than the periphery of the end of the container I.

The base 5 has a cylindrical part 6' having a surface I of conducting material which screws into, and makes electrical contact with, the 30 threaded contact sleeve III of the socket 9. The base 5 has a button contact 8 which makes contact with the contact button II'of the socket 9. The contact elements I and 8 of the base 5 are connected by current leads with the pairs of elec- 35 trodes 3 and 4. The contact elements III and II of the socket 9 are connected to the terminals of a suitable current source. Said electrodes 3 and 4 are electrically connected together as shown in the drawing and the cathodes 3 are heated to an 4 electron emitting temperature by the discharge current. When desired the cathodes 3 are heated to an electron emitting temperature by a separate heating current, in which case the number of contact elements on the base 5 and the socket 45 9 is increased.

The container I is surrounded by a double walled jacket I2 which acts as a heat'conservator to reduce the radiation of heat from said con tainer -I and thus to maintain an efiective metal 50 vapor pressure in said lamp device. The space between the walls of said jacket I2 is evacuated or filled with a gas having poor heat conductivity characteristics at a pressure lower than atmospheric pressure. Said cover I2 is provided with a 55 support ring cemented thereto and threaded on theinside to screw onto the socket 9. The entrance of cold air between the container I and the inner wall of the jacket I2 is thus prevented. The above described lamp unit is or simple structure, is inexpensive to manufacture, and is an efllcient source of high intensity light.

While I have shown and described and have pointed out in the annexed claims certain novel features of the invention, it will be understood that various omissions, substitutions and changes in the forms and details of the device illustrated and in its use and-operation may be made by those skilled in the art without departing from the broad spirit and scope of the invention, for example, the socket 9 is provided with a thread part to screw into another socket and is thus used as an adapter, when desired and other types of bases, such as a bayonet base,is provided for the lamp device, when desired.

What I claim as new and desire to secure by Letters Patent 01' the United States is:-

1. A gaseous electric discharge device comprising a curved container having the ends thereof in adjacent positions, each of said ends having a pinch part protruding therefrom. said pinch parts being in the same plane.

2. The method 01' manufacturing curved, tubular containers for gaseous electric discharge lamp devices which comprises the steps of bending a glass tube until the ends thereof are in adjacent positions, inserting the electrodes and electrode leads into the open ends of said container, heating said ends to their softening temperature and then pinching both or said ends simultaneously.

COBNELIS BOL. 

